Grassland Arthropods of Canada
Exploring the diverse world of grassland arthropods in Canada's endangered prairie ecosystems
Beneath the vast, windswept skies of the Canadian prairies lies one of the world's most endangered ecosystems. While many envision grasslands as serene, empty landscapes, they are in fact teeming with life—a significant portion of which remains invisible to the casual observer.
Canada's grasslands are the unacknowledged foundation of agricultural prosperity, biodiversity hotspots, and crucial carbon sinks, yet over 80% of native Prairie grasslands have been lost since European settlement 4 7 .
This loss threatens not just iconic species like burrowing owls and swift foxes, but an entire hidden universe of arthropods—the insects, spiders, and other invertebrates that form the ecological backbone of these habitats. Recent scientific efforts have revealed that these creatures are not merely inhabitants but essential engineers of the grassland world, playing critical roles that sustain both natural ecosystems and human agriculture 2 3 .
Canada's grasslands, primarily located in the Prairies Ecozone across southern Alberta, Saskatchewan, and Manitoba, represent the northernmost extension of the Great Plains of North America 2 . This ecozone features a continental climate with long, cold winters and hot, short summers.
of the 443,000 km² of the Prairies Ecozone has been converted to farmland
0.3-0.5 m height, 260-375 mm average annual precipitation
0.8-1.2 m height, 375-625 mm precipitation
1.8-2.4 m height, 625-1200 mm precipitation
Less than 1% remaining in undisturbed state 2While large mammals and birds often capture conservation attention, arthropods constitute the unseen majority of grassland biodiversity. The Biological Survey of Canada initiated a landmark project in 1979 to document these organisms before their habitats vanished entirely 2 .
of native plants and agricultural crops
through predation
through decomposition
for birds, mammals and wildlife
Recent DNA barcoding studies have revealed that arthropod diversity in Canada may be vastly greater than previously imagined—potentially exceeding 100,000 species nationwide, with more than 25% occurring in the Prairies Ecozone alone 2 .
To understand how landscape changes affect these crucial organisms, researchers conducted a massive study of beneficial arthropods across Western Canadian agricultural landscapes and adjacent mountain ecosystems from 2015-2019 5 .
The study employed passive trapping methods across 409 sampling sites in two focal areas: the Canadian Rockies (70 sites) and the agriculturally intense Canadian prairies (339 sites) 5 .
| Ecosystem Type | Sampling Sites | Primary Traps |
|---|---|---|
| Montane Region | 70 sites | Blue vane traps |
| Prairie Region | 339 sites | Blue vane traps, colored cup traps, pitfall traps |
The research compiled an astonishing 232,899 specimens across five arthropod orders and 26 families, with 92.4% identified to the species level 5 .
| Arthropod Order | Common Groups | Identification Success |
|---|---|---|
| Hymenoptera | Bees, ants, wasps | 95.6% of specimens |
| Diptera | Flies, mosquitoes | 0.15% of specimens |
| Araneae | Spiders | 93% of specimens |
| Opiliones | Harvestmen | 19.9% of specimens |
Specimens Collected
Identified to Species Level
The data revealed that non-crop habitats embedded within agricultural landscapes serve as essential refuges for beneficial arthropods 5 . These areas—including road margins, pothole wetlands, and native prairie patches—provide critical resources that support both pollinators and natural enemies of crop pests.
Studying these often tiny and elusive creatures requires specialized tools and techniques. The methodologies refined through decades of research have enabled scientists to document arthropod diversity with increasing precision.
Passive traps that attract flying insects. Highly effective for capturing pollinators like bees and flies 5 .
Cups painted fluorescent colors to attract insects. Target pollinators; typically placed at crop canopy height 5 .
Cups buried flush with ground surface. Capture ground-dwelling arthropods like beetles and spiders 5 .
Species identification using genetic markers. Revolutionized diversity estimates; revealed many cryptic species 2 .
Protection goal by 2030 through the Prairie Grasslands Action Plan
An area six times the size of Calgary 4Emerging evidence suggests that moderate grazing can increase arthropod diversity and benefit certain arthropod guilds, while crop rotation creates annually shifting landscape patterns that affect both pest and beneficial arthropods 6 .
The Nature Conservancy of Canada has launched an ambitious Prairie Grasslands Action Plan aiming to protect 500,000 hectares by 2030—an area six times the size of Calgary 4 . Such efforts recognize that protecting grassland arthropods isn't just about conserving insects and spiders; it's about safeguarding the essential ecosystem services they provide, from pollination to natural pest control.
The hidden world of grassland arthropods represents one of Canada's most significant yet overlooked natural heritage treasures. These small creatures form the foundation of healthy grassland ecosystems, supporting everything from soil fertility to agricultural productivity.
As research continues to reveal the astonishing diversity and ecological importance of these organisms, it becomes increasingly clear that their conservation is not merely a scientific priority but a practical necessity. The future of Canada's grasslands depends on our ability to recognize the value in the small and seemingly insignificant—to understand that the health of the entire ecosystem literally hinges on the creatures beneath our feet.
Through continued research, sustainable agricultural practices, and targeted conservation efforts, we can ensure that these vital ecosystems and their intricate webs of life continue to thrive for generations to come.